Long time back I had built a water level Indicator and had installed it at home , some of my relative saw it and they told me to build one for them, i made only two and didnt do after that ,the proto had a lot of flaws,l like the wire on the terrace getting weak because of sunlight and many more

My mom was telling me to do it wirelessly
so i came across this GSM one

If i want to build a water level indicator with GSM
that will give me call, indicating the tank being filled

Hi John Rodrigues
Thats one simple old project which has not been conquered by anyone perfectly. I still dont see any reliable water level controllers or indicators used and adopted extensively. Its in my to do list.

The wired method of doing it is problematic. Wireless is the way to go. If you want to do it as a commercial product then go for long range communication devices like LoRa or Long range Zigbee. Because the devices can operate on battery and run for long time and the long range is necessary because these devices can be on single floor buildings as well as some one might want to use them for apartments which are quite tall these days and the signal from top floor or syntex tanks will not reach the ground floor, where normally the motors or the controlling circuit are present. Although it might find attractive , I would not use GSM devices for this application because GSM modules are power hungry and need a constant source of power to recharge their battery. They draw around 50mA current when in normal operation and 2A current when transmitting data and 1mA in sleep mode. Devices like LoRa can run in active or normal operation at less than 1mA and transmit at 25mA. There is no bootup time involved in LoRa or Zigbee devices. We can keep these devices powered off all the time and immediately turn them on send data and shut down. Its not the case with GSM module, they need atleast 45 seconds to boot up and acquire network. During this 45 seconds they consume lot of current. But still you can use them if you want to go for call based system.
And the detection method used for measuring the water level also makes a significant difference in power consumption.
There are lot of options,
Many people try to use conductivity method and fail because passing current through water will corrode the electrodes due to electrolysis.
There is ,
Capacitance method (high resolution),
Pressure method (I am designing something based on this). (High resolution)
Float switches. (Low resolution, Depends on number of switches used)
Float ball or Angle arm (High resolution, Limits the type of tanks to be supported)
Ultrasonic (High resolution, Unreliable)

I suggest you plan this based on the distance to be supported. Always choose the technology which will reduce the gap between your device and the user (Smartphone),
The shortest are ,
Bluetooth,
GSM SMS,
GSM GPRS

John Rodrigues…Can i know why do you prefer water level indicator than water level controller?There are lot of companies already manufacture these products and as Ravi Pujar said i don’t think they hold the market…So it will be a nice option if we develop a product minimizing all their faults and errors …START THE PROJECT!!I am in!!

John Rodrigues You did a perfect job as we discussed.
Well, coming to the topic, conventional methods were there for water level indicator like putting an alarm so that it buzzes when the tank becomes full or empty. Nowadays, classical methods are used like water level controller as Mohammed Shahi said. There are different types of controllers available like simple ON/OFF 2 level switch, PID Controller, etc… Using PID Controller, one can also control the flow rate or adjust the total time of inflow/outflow. We can use the PID controller in between the Arduino and final control element (Valve) and the task gets over.
I hope this helps you.